A building for the institution of the Guardianship was supposed to be erected by Shoghi Effendi on Mount Carmel

Upon each of the graves of these holy souls Shoghi Effendi erected, in white Carrara marble, circular pillared and domed monuments, representing a Roman—renaissance adaptation in style of their prototype, the famous monument to Lysicrates which was built in Athens over two thousand years ago. Above them, on the steep incline of the mountain, he laid out a handsome, broad, sweeping are, more open in curve than a semi-circle, beyond which would be erected the future international administrative buildings of a World Faith. Having thus envisaged a major architectural scheme, he followed his so long as His own fixed policy of commencing with the easiest and most feasible part of his plan first, In other words, although he contemplated a series of capacious buildings abutting on his are, a building for the institution of the Guardianship, one for the Universal House of Justice, one for the Hands of the Cause, a library, and others, he decided to commence with a suitable edifice to house the collection of sacred and historic relics and documents collected at the World Centre and at that time preserved in two separate places.

-Ruhiyyih Khanum

https://bahai.works/Bahá’í_World/Volume_13/The_Completion_of_the_International_Archives